1. Field of the Invention
This invention relates to trailer hitch couplings of the ball and socket type and more particularly to an improved coupling wherein the two coupling members are automatically and positively locked against possible separation whenever they are interconnected and without the need for any intervention on the part of the user.
2. Description of the Prior Art:
A common and widely used coupling for trailer hitches consists of a ball member and a socket member having a recess adapted for receiving and engaging the ball member, with the ball member being attachable to the rear end of the hauling vehicle and the socket member to the tongue of the trailing vehicle. A latch is provided on the socket member which is manually movable to engage the ball member and to lock the members together when the coupling is in use. Likewise, the coupling can be disengaged by manual movement of the latch. Typical examples of such type trailer hitches may be found in U.S. Pat. No. 2,726,099 (reissued as U.S. Pat. No. RE. 24,362) and U.S. Pat. No. 2,971,777.
Although these prior trailer hitch couplings are quite satisfactory when properly used, there is always the danger that the user will forget to place the ball latch into final locking position before proceeding to his destination. When this occurs, the likelihood is that the coupling members will become disconnected while the vehicles are in transit which could result in a serious accident.
This problem has received attention but the means previously proposed for overcoming it have not been entirely satisfactory. For example, U.S. Pat. No. 2,855,222 describes a self-locking ball and socket coupling for trailers. However, the mechanism by which this was achieved is quite complicated and requires so many difficult to fabricate parts that construction would be difficult and costly. U.S. Pat. No. 2,726,099 also represents useful background art.
It is therefore an object of this invention to provide an improved self-locking ball and socket coupling for trailers in which the parts are few and simple in configuration and easily manufactured and assembled.